Prepared demolition charge



June 29, 1954 c. P. HAGENSEN PREPARED DEMOLITION CHARGE 2 Sheets-Sheet 1 Filed March 28,. 1945 INVENTOR CARL R HAGENSEN s Q nlln 5813.: 1.55

ATTORNEY C. P. HAGENSEN PREPARED DEMOLITION CHARGE 2 Sheets-Sheet 2 CARL I? HAG'ENSEN BY k L ATTORNEY June 29, 1954 Filed March 28, 1945 Patented June 29, 1954 UNITED STATES PATENT OFFICE (Granted under Title 35, U. S. Code (1952),

sec. 266) 4 Claims.

This invention relates to demolition charge packs for use in demolishing tough structural elements, especially those which have a small girth such as steel beams, wire cables, pilings, rails, etc. One specific application of the use of the present device is to quickly clear obstructions, built by the enemy against the movement of motorized traflic, in offensive warfare.

The object of this invention is to provide suitable demolition charge packs which are simple and easy to make and may be quickly applied to any form of structure which it is desired to sever at a particular place thereof.

Another object is to provide a demolition charge pack which is semi-flexible so that it may be more closely applied around an object of small girth which it is desired to break.

Another object is to provide a demolition charge pack with suitable attachments, whereby it may be quickly adjusted in place around obstruction elements which it is desired to clear.

Other more specific objects will become apparent as this description proceeds, having reference to the accompanying drawings, wherein Fig. 1 is a perspective view of one form of the present invention as it appears from the detonating cord side;

Fig. 2 is a perspective view of the same pack as it appears from the lashing rope side;

Fig. 3 is a sectional perspective view of the explosive composition unit used in this pack, showing how the detonating cord is embedded therein;

Fig. 4 is an exploded perspective view of the demolition charge pack units partly in section;

Fig. 5 is a section taken on the line 55 of Fig. 2; and

Fig. 6 is a detail view showing the mode of use of a flexible form of pack applied to an angle iron beam.

Referring to the several views of the drawings, wherein like parts are designated by the same numerals, the demolition charge I may be formed in a wooden form approximately 1 /2 inch deep by 2 inches wide by 12 inches long.

The detonating cord 2 is first out into lengths approximately 11 feet long, both ends being dipped in molten beeswax or asphalt to seal them against moisture. One end 3 of the cord is looped back and forth to form five strands 4 about 12 inches long, leaving a six foot lead, usually called the explosive lead. The loops are tightly wrapped with approximately six wraps of friction tape 5 at the lead end, five wraps 6 at the other end, and three wraps l in the middle. The bundle of loops then becomes a booster of which one of the advantages lies in its being an integral part of the detonating cord.

A wrapper consisting of a single sheet of parafiin lining paper, Northern Craft No. l or its equal, approximately 8% inches by 15 inches is inserted into the wooden form. The lined form is then filled to half its depth with a demolition charge. The looped cords are then laid in the center of the half-filled form, and the remainder of the form is filled with addition composition, making sure that the cord is completely surrounded by the composition. The form is then closed and pressed to form a single block I, with the six-foot lead end extending out from the center of the end of the block. The lining paper is folded over the composition block which is then removed from the form, and the paper secured in two places with 1 by 4 inch strips of masking tape or the like.

The canvas bag 8 may be made of cotton canvas duck No. 10, or some similar material, by cutting the material into proper shape and sewing along one corner 9, as shown, leaving open flaps ID, I I, I2 and I3 at one end, and providing a grommet [4, which may have an opening [5 of about {a inch in a diameter and which may be made of zincplated brass or steel, in the other end. Another grommet I 5 of the same type as above is inserted near the end of one of the flaps l3 on the wider side of the open end; and along the same side of the bag there are three quarter-inch strips of webbing I! tackstitched thereto at spaced intervals. On the opposite wide side of the bag at the closed end thereof, a strip of printers webbing 2 inches by 1 inch is doubled over to form a loop l8 and sewed to the corner of the bag.

A steel sheet material or equivalent flat stock of about inch in thickness is cut out in the form of a hook I9, as shown, the outside edges being rounded off except at the sharply tapering V-cut which constitutes a raw-edged wedge crotch 20. The surface of this hook is cleaned, dried and freed from mill scales and loose rust, and then greased. Two coats of corrosion-resistant plastic film may then be applied.

A piece of inch webbing 2| about 5 /2 inches long is then passed through the hole in the hook I9 and its ends sewed together as shown at 22, forming a loop which is passed over the long flap at the open end of the bag. The end 24 of a piece of quarter-inch braided sash-cord 23 about 3 feet long is passed through the web loop [8 at the closed end of the bag and secured to the cord at 25 to form the short loop. The

3 middle of a 3-foot piece of A; inch soft braided cord 26 is tacked at 21 onto the same side of the bag where the canvas loop I8 is formed, but close to the opposite end of the bag.

The lead end of the six-foot detonating cord extending from the charge is inserted through the grommet [4 in the closed end of the canvas bag from the inside, then the charge is inserted into the bag. The webbing loop 2| holding the hook, having first been slipped over the flap [3 with the grommet iii, the flaps are closed over the end of the bag, flap I3 uppermost, sliding the hook is into position as shown in the drawings, and the soft-braided cord 26 is passed through the grommet l6 and tied securely around the bag to hold the flaps closed. The end of the detonating cord 2 which, as previously indicated as being of appreciable length, is passed ba'ck and forth under the strips of webbing I! which comprise storing means in loop form on the side of the canvas bag, making sure that the free end 3 of the lead extends out free of the stowing means near the closed end of the bag. The demolition charge pack is then ready for use.

Fig. 6 shows one mode of application of the demolition charge pack around an angle iron beam 28. The application is made by placing the charge around the outer corner 29 of the angle iron beam at the point where it is desired to sever it, the sash-cord 23 and hook I9 are pulled towards each other, the sash-cord being inserted into the V-cut of the hook so as to provide a secure grip therein. The detonating cord may then be pulled out by its end 3 and attached to a primecord trunk line or directly to the charge set-off means. Application to-other structures of similarly small girth is made in a like manner.

It may be seen that these charge packs are made in a convenient form, so that a number of them may be conveniently carried in a sack or harness means fitted for carrying over the shoulders. A sack containing twenty'of these packs will weigh approximately 51 pounds and is a convenient size for carrying by one person, who can readily apply the packs one at a time in proper places without taking off the sack.

Various modifications in the size and arrangement of the parts maybe made in these demolition charge packs without departing from the spirit and scope of the present invention as defined in the appended claims.

The invention describedherein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

l. A demolition charge pack comprising an oblong-shaped bag made'of canvas or other like material, a block of detonating composition packed therein having several loops of a detonating cord placed inside thereof, a length of said detonating cord extending from one end of said block through a grommet in the closed end of the bag, the other end of said bag being open for the insertion of said charge and having flaps for closing it, one of theflaps being'provided with means for tying around the pack to hold the bag securely closed, webbing means on the side of the bag, under which the loose end of the detonating cord is looped back and forth, having its end extending in the direction of the closed end of the bag, so that it may be quickly pulled out of place under the webbing, a steel sheet hook attached by a piece of webbing looped around the closing flap and having a V-cut in its hook portion, and a piece of sash-cord fastened to the closed end of the bag for quick application around an object to be severed by the demolition charge and for insertion in said v-cut of the hook to hold the charge in place.

2. A demolition charge pack comprising a canvas bag closed at one end and open at the other, having flap means for closing the open end, provided with means for tying the open flaps in closed position around the bag, a steel sheet hook having a narrow V-cut therein fastened by a loop of webbing around one of said flaps, a sash-cord attached to the closed end of said bag for wrapping around an object and inserting in said narrow V-shaped cut to fasten the bag in place, a detonating cord, and a demolition charge composition for insertion in said bag having one end of the detonating cord embedded therein, the other end of said cord being passed throughan opening in the closed end of said bag and looped under webbing means on the outside of the bag for easy withdrawal by pulling on the extreme end thereof which is positioned adjacent said closed end.

3. A demolition chargev pack consisting of a long detonating cord, said cord being repeatedly looped at each of its ends to provide a bundle of re-entrant loops at each end integrally connected by an unlooped medial cord portion, a block .of explosive composition in which one of the bundles of loops is fully and intimately bonded, leaving the medial cord portion and its attached bundle of loops exposed, a container in which the block is packed, having an opening at one end through which the medial cord portion emerges, and webs bridging one side of the container at a number of places, behind which the exposed and otherwise loose bundle of loops is temporarily stowed for a quick unraveling.

4. A demolition charge pack comprising a container having a volume of explosive substance therein, a tie-cord extending freely from one end of the container for looping around an object to be demolished, and receiving means carried by the other end of the container, to which a portion of the tie-cord is securable with a friction grip, said receiving means including a fiat-stock hook having a sharply tapering raw-edged wedge crotch therein.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 99,665 Gomez Feb. .8, 1870 152,053 Striedinger June 16, 1874 174,868 Smith Mar. 14, 1876 356,651 Linton Jan; 25, 1887 673,821 Rahn May '7, 1901 698,865 Smith et al Apr. 29, 1902 905,336 Lheure Dec. 1, 1908 1,042,6 i3 Brunswig Oct. 29, 1912 1,515,418 Smith Nov. '11, 1924 1,493,921 De Blasio May 13, 1924 1,835,666 Mitchell Dec."8, 1931 1,890,726 Farren Dec. 13, 1932 2,087,209 Lahey July 13,1937 2,295,854 Lindsley Sept. 15,1942 

